The present invention relates to a method and system for operating a navigation system, and more particularly to a method and system for geocoding a query for geographic location information using prior usage patterns.
Navigation systems are available that provide end users with various navigation-related functions and features. For example, some navigation systems are able to determine an optimum route to travel along a road network from an origin location to a destination location in a geographic region. Using input from the end user, the navigation system can examine various potential routes between the origin and destination locations to determine the optimum route. The navigation system may then provide the end user with information about the optimum route in the form of guidance that identifies the maneuvers required to be taken by the end user to travel from the origin to the destination location. Some navigation systems are able to show detailed maps on displays outlining the route, the types of maneuvers to be taken at various locations along the route, locations of certain types of features, and so on.
In order to provide these and other navigation-related functions and features, navigation systems use geographic data. The geographic data may be in the form of one or more geographic databases that include data representing physical features in the geographic region. The geographic database includes information about the represented geographic features, such as one-way streets, position of the roads, speed limits along portions of roads, address ranges along the road portions, turn restrictions at intersections of roads, direction restrictions, such as one-way streets, and so on. Additionally, the geographic data may include points of interests, such as businesses, facilities, restaurants, hotels, airports, gas stations, stadiums, police stations, and so on.
In order to provide some of the navigation-related functions and features, the navigation system obtains a query for geographic location information, such as address information. For example, the query is 425 West Randolph, Chicago. Typically, the navigation system geocodes the query. Geocoding is the process of finding associated geographic information, such as geographic coordinates of latitude and longitude, from geographic information of a different format, such as the query comprising the street address. With the geographic coordinates, the navigation system can provide navigation-related functions and features, such as a detailed map showing the geographic location information corresponding to the query on a display.
Although navigation systems provide many important features, there continues to be room for new features and improvements. One area for improvement is how the geocoding process resolves ambiguous queries. Ambiguities often happen because of misspellings or the queries have varying formats with different abbreviations for street address information, such as “Street,” “St” “West,” and “W.” When there are ambiguities, the query may not provide an exact match with reference geographic data of a geographic database; rather, there are several candidate matches. For example, if a user enters “425 Randolph, Chicago” possible candidate locations include “425 West Randolph Street Chicago Ill.” and “425 East Randolph Street Chicago Ill.” Thus, there is a need to accurately and efficiently determine which of candidate locations to present to the user.